Numerical investigation on hydrodynamics of gas-binary particles flows using a second-order-moment turbulent model

A binary-particles Reynolds stress equation is developed on the basis of single second-order-moment turbulence model. In this model, particle–particle two-phase fluctuation velocity correlation transportation is proposed to fully reflect their anisotropic characters, as well as each of particle interaction with gas phase is taken into account. Swirling gas-particle flow experiments data is used to validate this model simulation in term of the reduced codes of the mono-disperse particle gas-particle flows. Numerical simulations are performed for the gas-binary particles mixtures turbulent flows and results shows that the axial Reynolds stress in near wall regions is approximately 3.0 times greater than the tangential direction and the tangential Reynolds stress in central axial region is approximately 5.0 times greater than the axial direction. The Reynolds stress in the axial direction and tangential direction are redistributed due to binary particle–particle collision. The ratio kinetic to particles collision contributions in binary mixture system are varied with the different particle density and the diameter size compositions.

► A new binary-particles Reynolds stress equation is developed. ► Anisotropic particle–particle fluctuation velocity correlation is fully considered. ► Reynolds stresses are redistributed due to binary particle–particle collision. ► Particle density and diameter size change collision contributions.